echoed on your skin
by Trinity Everett
Summary: He finds his match is smart, her humor sharp, and the desire just to meet her for real nearly overwhelms him. He doesn't. It isn't the right time. But he asks her to call him Rick, and in return, she asks him not to call her Katie any longer. It's Kate, she says. - A Caskett Meeting AU for CastleFanficMonday
**echoed on your skin**

 _A Caskett AU for CastleFanficMonday_

 _Based on the prompt: Soulmate AU where, when you write something on your skin with pen/marker/whatever you want, it will show up on your soulmate's skin as well._

* * *

He's eight years old the first time his Soul Marker shows up.

It happens on a Saturday in the middle of November and, at first, all he notices is that it is _cold_ in his bedroom. The wind rattles the world outside, seeping through the gaps along the windows and under the doors to bring the chill inside. His mother does what she can for them, more than enough, but she can't help that their apartment is drafty. So he doesn't complain, he doesn't whine in the early morning air, he just draws his blankets closer to his ears.

The dark smudge on his palm catches his attention then.

It isn't large, definitely nothing impressive, just a smear of black on his hand. Like he had been playing in the dirt in the middle of the night. When he shows his mother later that morning, she just smiles and presses a wet kiss to his forehead.

Not content with that answer, Richard Rodgers swipes the affection from his skin and demands to know more.

Ever indulgent, Martha takes his hands, tickling the mark on his palm until he giggles.

"When babies are born, their handprints and footprints are taken. Congratulations, kiddo, your Soul Match has arrived in the world."

He's appalled; his Soul Match is a _baby_? There is no way.

For a moment, he considers the possibility that his mother is pulling his leg, playing a trick on him to get back at him for using her favorite bubble bath as dish soap, but there is only gentle humor in her eyes. Only relief.

Relief that he has a match.

Not everyone does, he knows. His mother doesn't. There are times when she comes home from work and he swears he can see his own doodles on her skin, covered by layers of stage makeup, but it's the bond of a parent to her child, not a true Soul Match.

He can't help but wonder why _he_ has one and she doesn't.

The next Monday after school, he goes to the library and gathers as many books about Soul Matching as his thin arms will hold. He reads as many as he can before his mother comes to pick him up, checking out the rest and shoving them into his backpack. In the end, the entire idea makes a bit more sense. It's something precious, something special, like being a superhero. Which doesn't sound so bad really.

But still, a _baby_? He can't be matched with a baby.

* * *

He's fourteen the first time his match makes contact. Over the years he has grown used to splotches of color appearing on his body – finger paints, or paint of some kind he's always assumed – but this is different.

This is a greeting in two blocky, childlike letters.

 _Hi_

It takes him four hours to respond, most of which he spends freaking out. A week earlier, he had forgotten about the person on the other end of this bond, and scribbled Vanessa Carlisle's number across his palm so they could talk about their math homework and plan a date to the movies. Had he broken some rule of the Matching?

Still, he replies. He offers his match a simple hi in return.

She draws a smiley face in the space between her index finger and thumb, branding him with the same cheer for almost two days.

He grumbles if anyone asks, because (at least according to the rules of the eighth grade) he is too cool for smileys, but secretly he likes it.

* * *

He doesn't hear from her again, not really, until he's twenty. Throughout high school and the early days of college, he had been careful not to do more than doodle on his skin, lest he actually break some rule about forcing contact before the "proper" time, so it's jarring to see actual words appear on his skin.

 _I'm Katie. Who are you?_

The question makes him laugh. It's brash, it's bold, but it is enough to make him respond without weighing the pros and cons of doing so.

 _Ricky._

Most days he still feels like Ricky Rodgers, not Richard Castle, the man he's trying to be, so he gives her the nickname everyone had for him in boarding school.

She doesn't say anything else that day, but her occasional drawings become more frequent and more detailed as the weeks go on. In return, he scribbles additions with a sure hand, painting them both with silliness.

He meets Kyra a few months after Katie makes contact. She isn't his match, obviously, but she is fun and sweet. She never seems fazed that he is on the verge of literary stardom after publishing his first novel, or that he occasionally finds himself engrossed in drawing on his body to amuse someone he has never met.

Their relationship is easy, but they both know it will end at some point; they are still matched to other people. So after nearly three years, when an invitation to London appears on her arm, Kyra packs her bags and he doesn't try to stop her. It's the right time for her.

She sends him a letter a year and a half later, gushing about her newborn daughter and wishing him all the same happiness she has found.

For the first time since his Soul Marker appeared on his hand, being matched doesn't feel like a gift. It feels like a curse, the dangle of a carrot he can never quite grasp no matter how hard he tries.

His mother reminds him to be patient, promising that his time will come, but the tugs of loneliness and envy make it difficult to keep his chin up.

Hope starts to return the day Katie scribbles a declaration of boredom on her palm and challenges him to a game of forearm hangman. After that, they play often, they chat often. He finds his match is smart, her humor sharp, and the desire just to _meet_ her for real nearly overwhelms him.

He doesn't. It isn't the right time.

But he asks her to call him Rick, and in return, she asks him not to call her Katie any longer.

 _It's Kate_ , she says.

* * *

He's about to turn twenty-six the day she asks what he thinks of being matched, both in general and to her. It's the first time they have acknowledged their situation to one another, and the short conversation that follows bolsters his spirit; having a Soul Match is odd for them both, but they will make it through.

Just weeks later, he finds himself giving her a hard time about the compass rose tattoo that appears on his hip. It is small, not what he would have chosen for himself, and at first he is a little perturbed to know it will be on his body forever. As time goes on, he likes the idea behind it more and more; the shared compass orients them toward one another.

He finds that comforting, grounding. Even as his professional life takes off, his popularity grows, and he becomes something of a golden boy in some literary circles, the marking on his hip is a reminder that there is more to him than that. He has a Soul Match he will one day meet.

Still, he can't help but push the envelope a bit. He doesn't just sign books, he scrawls his name against skin, hoping to one day see that signature echoed on his own body.

A year passes, and it never does.

When his match writes flight times on her palm, he finds out why: she's in California, San Francisco to be exact. He doesn't know if she's there for a visit, or for school, or for some other reason, and he isn't sure if he should ask, but he offers his own input for her travel.

 _Don't take the red-eye. You'll be a zombie._

She draws a stick figure in response, complete with a conversation bubble crowing for brains. It makes him chortle in the middle of a coffee shop.

 _Thanks._

The single word of gratitude warms him, making him silly as he orders another cappuccino and settles in to write.

* * *

He's twenty-seven and fresh off a seven-hour writing binge when his name appears on his arm, her handwriting shaky in ways he has never seen before, not even when they were little. Scrubbing the grit out of his eyes, he grabs his pen to answer her. He never makes her wait if he can help it.

 _I'm here. You want a tic tac toe rematch now?_

Worry seizes his heart when she doesn't respond within a few minutes. Is she in trouble? Is she _hurt_? Not for the first time, he wishes he knew more about her, about the woman the universe has decided is his _soulmate_ , because right now he has next to nothing to go on.

 _Kate, are you okay?_

Again, he gets no reply. Pushing away from his desk, he makes a lap around his office. Then another one. Each time he passes his computer, he checks his arm for another message. Each time there is none.

Damn it; clearly, she needs him and yet he's left sitting on his hands, impotent to do more than try to communicate through his skin.

He needs to do more. He needs to _be_ there for her, beyond this. More than this.

The thought has him slumping into his desk chair and scraping his hands over his face.

Finally, _finally_ , she replies, but there is nothing playful or light about her answer.

 _No. My mom died tonight._

Oh, God.

 _I - can you come? I need you, Rick._

He's already standing, already shaking his mouse to pull his computer from sleep so he can book a plane ticket to wherever he needs to go. Maybe it's the right time for them to meet, maybe it isn't; he doesn't give a damn. The hell with whatever cosmic rules they're supposed to be following, if there are any at all.

 _I'm on my way, just tell me where._

He gives her his number a moment later, even as his muscles coil to take him to his bedroom to pack a bag. Packing will keep him busy while he waits for her to send him an address.

Hell, he doesn't even need that; he'll take a city and a state and work his way to her from there.

His phone buzzes before he can push away from the desk, boasting a new SMS from a number he doesn't recognize.

A New York number.

His heartbeat thuds against his temple as he reads the address. Holy shit. She's from New York. She's _in_ New York.

Has his match been here the entire time?

He runs almost the entire way to her, his steps refusing to slow until he sees a figure push herself off the steps of the West Village apartment building he's approaching.

It's inane, but the first thing he thinks when he sees her – his Soul Match – is that she's tall, lithe. Her hair is dark, at least in the light from the streetlamp, tousled at the roots from where she no doubt keeps running her fingers through it.

"Kate?" he asks, throat tight. God, he can't even imagine what she must be feeling right now, how stunned, how distraught she must be. "Hey, hi, it's uh, it's me – Rick."

Yelping, she flings her arms around him, nearly toppling from the final stair to get closer. He rocks, but manages not to send them both crashing to the pavement.

"You came. Shit, you came." Awe coats every word, and he finds himself holding her tighter, pressing his lips to her temple.

"Of course I came. You're my –" he exhales, palming the back of her head. "You're my best friend, Kate. Not just my match."

She is, without a shadow of a doubt. She's the one person he can poke – in the figurative sense – at any time about anything. She's the one person who knows him best, even if it's only through doodles and text. She is all of those things for him, and he will be here for her. No matter what.

Her face presses deeper into his neck, tears dampening his skin.

"I've got you," Rick murmurs, feeling his own heart shatter as she falls apart. "I've got you."

She nods finally, sucking in a hitching breath. "Can you stay? I – I mean I know it's weird, but –"

"As long as you need me to," he promises without hesitation. "As long as you need me to, Kate."

* * *

He's just days shy of turning thirty-three when he proposes.

By all accounts, it is an ordinary Thursday morning, but when he wakes up beside her, their legs entwined, he just knows the time is right. It's been five years since her mother's death, and he hasn't left her side. No matter how raw the sadness, the anger, the desperation, they have been together, learning and protecting one another. Soul Matched or not, he wants to make the promise to her that it is forever.

He loves this woman above everything else, even writing. She is the last person he thinks about every night as he closes his eyes and the first one on his mind when he wakes each day. He is proud to be with her, proud to be able to scribble his love for her on his arm in the middle of an afternoon and know she'll see it when she rolls up her sleeves as she changes out of her uniform at the precinct.

She makes each moment better than the one before, and she never quite seems to realize how her presence is cherished. How much _she_ is cherished.

But maybe his plea will help make his case.

She's still sacked out when he sets things in motion, oblivious to the design appearing at the base of her ring finger.

He slips out of bed once his artwork is finished, eager to start the coffee. Kate hums, rolling into his abandoned spot, nuzzling her cheek against the dent his head left on the pillow. She doesn't wake, and that may be the only reason he is able to turn around and tiptoe out of their bedroom.

He takes his time with the coffee today, needing every flavor and every line in the foam to be just right. After everything they've been through, this needs to be perfect.

It will be perfect.

She's still in his spot when he returns, but her eyes lock on him the moment he crosses the threshold. She cradles her hand to her chest, fingers closed around her palm as if she's holding the secret in, holding the hope in for herself.

He offers a quiet greeting, setting the tray with their coffee and fruit on the chair beside the bed before perching in the open space the curve of her body has left for him.

"Thought you might still be asleep," he murmurs, leaning over to touch his mouth to her cheek, the corner of her lips, then finally her mouth.

"Wanted to creepy stare more?" she teases, clearing the gruffness of sleep from her throat a moment later. "Or wanted to finish setting this up?"

Her fingers open, splaying wide to show him the markings on her skin. The ring he had drawn is a pale comparison to the one in the drawer of his nightstand, but it's still enough to show her his intention.

Taking her hand, he smooths his lips over the design. "Do you know what I said the day my mother explained what my Soul Marker meant?"

Her brow furrows at the question, at how much of a non-sequitur it is, given what they both know he wants to ask her, but she plays along.

"No, what?"

"Why does my match have to be a _baby_ ," he breathes, laughing when her eyes brighten. "I was eight, and the idea of a match of any kind was foreign, let alone a match with an age difference like that."

Her fingers slip through his pressing their palms together. "Tell me about it. I knew you had to be older when you were writing down phone numbers and talking about homework and I was still working on addition problem sheets and worrying about Show and Tell."

Rick groans, dropping his forehead against hers. His match puffs a laugh, craning her neck for a kiss he gives freely.

"But once I got older, once we started to talk, it made me feel better knowing you were mine," she adds against his lips.

He nods his agreement. "Me too. Even when it sucked, when it felt like we would never get our time, you were still there."

Kate hums, squeezing his hand.

"You came running the night she died. Running, Rick. I think you win the 'being there' award."

"Wasn't even out of breath - well, too out of breath - either," he offers, knowing how hard it is for her to talk about still, knowing how much levity helps.

Her lips lift. "My hero."

Rick can't help but take another kiss, firmer this time, promising. "I can't imagine my life without you."

Kate shakes her head, palming his cheek. "Me either, babe."

"And I know even if we hadn't been Soul Matched, even if we hadn't met the way we did or when we did, I know I would feel the same. You would still be my best friend, and my partner in every way. So Katherine Houghton Beckett, will you -"

"Wait! Wait, wait." Tugging her hand free, Kate hauls herself up and reaches for the pen beside the bed. "Write it, too. Please."

Her eyes beseech him to understand, and he does; she wants to have it with her, even after this moment ends. Slipping the pen from between her fingers, he nods.

"Don't get this tattooed, okay? I can't guarantee my best penmanship right now."

The love of his life giggles, smoothing her lips over his jaw. "I already know what I'm getting done next, don't worry."

The tease distracts him just enough to stop his hands from trembling.

They watch the pen glide over his forearm, both swallowing hard as the question appears in the same spot on her body.

 _Will you marry me?_

"Kate, will you marry me?" he asks on a shaky exhale.

Her mouth lands on his, her lips moving in joyous confirmation even as her nimble fingers take the pen from his hand to brand the both of them with her answer.

 _Yes_.

* * *

 **Huge thanks to Lindsey, Callie, and Ally for letting me tease this fic and helping me brainstorm titles for it. Without you guys I would still be stomping my foot and heaving heavy sighs. <3**


End file.
